Expression and regulation of orphan receptor TR2 mRNA in germ cells of cryptorchid testis in rat and rhesus monkey

Expression and cellular localization of orphan receptor TR2 mRNA in relation to germ cell apoptosis in cryptorchid testes of rat and rhesus monkey have been studied by using in situ hybridization and in situ 3'-end labeling of DNA fragments (TUNEL). The results show that: (i) TR2 mRNA is specifically expressed in the germ cells, mainly in the spermatocytes, round and elongated spermatids. The expression level of TR2 mRNA varies with the seminiferous cycle, (ii) In the rat cryptorchid testes on days 3 and 5 after the surgery, the germ cells began to undergo apoptosis with no evident decrease in TR2 mRNA level. On day 7.5, however, most germ cells underwent apoptosis, while the expression level of TR2 mRNA declined markedly, and TR2 mRNA was rarely expressed on day 10 thereafter. (iii) On days 15 and 20 of the cryptorchid testes of rhesus monkey, TR2 mRNA was only expressed in a few of primary spermatocytes and the mRNA was almost undetectable on days 30, 45, 60. These results suggest that TR2 mRNA probably plays an important role in spermatogenesis and germ cell apoptosis.

Assemble of poly(aniline-co-o-aminobenzenesulfonic acid) three-dimensional tubal net-works onto ITO electrode and its application for the direct electrochemistry and electrocatalytic behavior of cytochrome c

Stable electroactive film of poly(aniline-co-o-aminobenzenesulfonic acid) three-dimensional tubal net-works was assembled on indium oxide glass (ITO) successfully, and the cytochrome c was immobilized on the matrix by the electrostatic interactions. The adsorbed cytochrome c showed a good electrochemical activity with a pair of well-defined redox waves in pH 6.2 phosphate buffer solution, and the adsorbed protein showed more faster electron transfer rate (12.9 s(-1)) on the net-works matrix than those of on inorganic porous or even nano-materials reported recently. The immobilized cytochrome c exhibited a good electrocatalytic activity and amperometric response (2 s) for the reduction of hydrogen peroxide (H2O2). The detection limit for H2O2 was 1.5 mu M, and the linear range was from 3 mu M to 1 mM. Poly(aniline-co-o-aminobenzenesulfonic acid) three-dimensional tubal net-works was proved to be a good matrix for protein immobilization and biosensor preparation.